As the core component of electro-hydraulic servo control system, servo valve is widely used in aerospace, precision machinery, automation equipment and other fields. Among them, the small flow servo valve is widely used in systems that need fine control because of its characteristics of small control flow, fast response and high control accuracy. However, due to its small working flow, weak control signal and higher requirements for accuracy, how to ensure its accuracy has become a key issue in the design and application process.
First of all, the optimization of structural design is the basis of improving the accuracy of small flow servo valve. Small flow servo valve usually adopts nozzle baffle or moving coil structure, and its internal structure is precise and the gap is extremely small. The matching relationship between hydrodynamic characteristics and electromagnetic characteristics should be fully considered in the design to avoid flow fluctuation and control distortion caused by unreasonable flow channel design. At the same time, the use of high stiffness and low friction materials and structural design is helpful to improve the response accuracy and repeated positioning ability.
Secondly, the accuracy of manufacturing and assembly is very important. Under the condition of small flow, the micron error between the valve core and the valve sleeve may lead to a significant decline in control performance. Therefore, it is necessary to adopt high-precision processing equipment and technology in the manufacturing process to ensure the dimensional accuracy and surface smoothness of key components; Cleanliness control and dustproof measures should also be strictly followed in the assembly process to prevent tiny particles from entering the valve body and causing sticking or wear, which will affect the control accuracy.
Thirdly, the cooperation of high-precision feedback and control system is also an important means to ensure the accuracy of servo valve. Modern small-flow servo valves are usually equipped with high-sensitivity position or flow sensors, and the control signals are adjusted in real time through closed-loop feedback, thus improving the stability and anti-interference ability of the system. In addition, advanced control algorithms such as PID control and fuzzy control can also effectively compensate the system nonlinearity and external disturbance, and further improve the control accuracy.
Finally, regular inspection and maintenance can not be ignored. Even a well-designed small-flow servo valve may lead to a decline in accuracy due to wear, pollution or aging during long-term operation. Therefore, a perfect testing mechanism should be established, and key parameters such as flow-pressure characteristics, response time and hysteresis of the servo valve should be tested regularly with high-precision testing equipment, and necessary cleaning, calibration or replacement should be carried out according to the test results.
To sum up, to ensure the accuracy of small-flow servo valve, we must comprehensively consider the structural design, manufacturing technology, control system and post-maintenance and other aspects. Only by strictly controlling every link can we ensure that the servo valve can maintain a high level of control accuracy in the whole life cycle and meet the strict requirements of modern precision control technology.